GRFX Help

Thank you for your interest in GRFX - Granular Effects.

GRFX is a granular audio effect plug-in for deconstructing incoming audio into grains with transposition, envelope shaping, rhythm generation and probabilistic capabilities. Its feature set lends itself to experimentation and shaping simple sounds into textures, patterns and ambiances.

The granulator engine is accompanied by four LFO modulators for additional expressiveness, as well as two post-granulator Multi-effect slots and two Sends (Delay and Reverb), making GRFX an agile granular playground for serendipitous accidents and unexpected ideas.

Contents

• Overview
• Granulator
• Harmonic Triangle
• Modulator Rack
• Effect Rack
• Patch Management

Overview

The GRFX interface is segregated into three horizontal regions. The granulator engine lies in the middle. Parameters regarding the “macro” properties of the sound - such as number of grains, buffer size and trigger frequency - are placed on the left half, while the right contains parameters controlling the individual grains’ aspects, such as their shape and size.

Dead centre of the granulator is the Harmonic Triangle, an interactive pad for controlling the pitch shifting of the grains. This element allows for creative tonal (and microtonal) effects, chord generation and shimmer effects. See Harmonic Triangle.

Under the granulator is the Effect Rack. The two leftmost effect slots are Multi-effects; each can be swapped for any effect from a list of eight different effect engines. To their right are the sends: a Delay and a Reverb. Unlike the Multi-effects, these are fixed and can work in series or parallel. The final slot is the Mixer, with volume controls for the individual signal paths, along with an output volume control and Dry / Wet. See Effect Rack.

The top of the interface contains the Modulator Rack, displaying two of the four available LFOs at a time. These are used to modulate the plug-in’s various parameters and create autonomous movements and behaviors. See Modulator Rack.

Granulator

The union of various simultaneous fragments made from incoming sound is the basis of this effect. The left half of the Granulator panel contains controls for the speed and number of grains being fired, providing control over the general "density" of the sound. Each grain reads from a buffer continuously recording the input audio, displayed in the top left corner of the granulator along with each grain’s position.

GRFX’s granulator engine fires the grains in cycles. The length of each cycle is determined by the Frequency parameter (located in the left half), meaning that a lower time will make grains fire faster. Every active grain is fired sequentially throughout one cycle; 5 grains with a Frequency of 100 milliseconds will result in a grain firing every 20 milliseconds. Toggling the switch underneath will synchronize the Frequency parameter to the host’s transport, letting you create patterns and rhythms.

Next to Frequency is the Offset parameter, which determines how far from the writing position the grains will start reading. Reading farther back will introduce an effect similar to a pre-delay. This parameter can be synchronized as well.

Both Frequency and Offset have dedicated Random controls. The Frequency’s Random control will randomize the trigger time of the grains, making them erratic rather than periodic. The Offset’s Random control randomizes the position in the buffer that grains will start from. A value of 50% will make grain play up to half of the buffer size back, while a value of 0% will start the grains as close as possible to the write position. Introducing randomness to the Offset is efficient in capturing different bits of audio from the buffer, making the output less homogeneous.

The Grains parameter determines the number of grains that will play per cycle. By controlling the Grains, Frequency and Offset parameters, and making use of their Random functionalities, you can easily meander between sparse, periodic sequences and dense sonic clouds.

The buffer display has the current position that input is writing to, represented by a brighter green line, and the multiple playing grains, shown by slightly dimmer lines. Under them is the waveform, continuously drawn as audio enters the plug-in.

This section is accompanied by four controls: Sync, Size, Division and a Freeze button. Size determines the buffer size - how long the buffer can record for until it wraps around - while Sync will synchronize the buffer size to a tempo-aware beat time, such as a beat or a bar. This proves useful for rhythmic material, such as drums.

Division slices the buffer into a number of regions and snaps the grain’s start position to those positions, creating rhythmic stuttering effects.

Freeze - represented by the snowflake icon - will stop the buffer writing, holding its current material until unfrozen.

The right side of the granulator is reserved for controls related to the individual properties of the grains. The Window and Shape parameters work together to shape the amplitude window of the grains, making them more abrupt, plucky, soft or ascending. Stereo introduces randomness in the location of each grain in the stereo image, creating a totally mono or wide soundscape.

Size is a synchronizable parameter that controls the grain’s play length. Note that a grain’s Size can not be larger than the Frequency, as that would cause the same grain to fire before finishing its playback.

The Route parameter is a unique probability-based routing control that determines the chance of each grain going down route A or route B. Route A goes through the Multi-effect slots, while Route B goes directly to the Mixer. Using the available effect engines and Mixer controls, this enables a variety of creative effects, such as mixing processed grains with unprocessed grains, introducing very sporadic effects, routing A and B to different sends, and creating a chance for grains to not fire.

Rev. Prob (Reverse Probability) introduces a chance for the grains to read from the buffer in reverse.

Parameters

• Frequency - Grain cycle rate. Every grain will fire once per cycle.
• Random - Randomization of the grains' firing times.
• Sync - Synchronizes the parameter to tempo-aware beat times.
• Offset - Grain reading position offset from the write position. Similar to a pre-delay.
• Random - Randomization of the grains' read positions in the buffer.
• Sync - Synchronizes the parameter to tempo-aware beat times.
• Grains - Number of playing grains.

• Buffer Size - Size of the input buffer that grains read from. A short size will result in grains always reading recent material, while a large buffer allows grains to read very far back.
• Buffer Sync - Synchronizes the buffer size to a tempo-aware beat time.
• Buffer Division - Slices the buffer into a number of regions. When enabled, the grains can only start reading from these pre-defined positions. The Offset's Randomp control will make grains snap to positions farther back in the buffer.
• Buffer Freeze - Stops buffer input, holding the currently recorded audio indefinitely.

• Window - Controls the edges of the amplitude window applied to each grain, making it start and end abruptly or smoothly with fades.
• Shape - Skews the amplitude window left and right, turning it into a pluck-like shape or a growing ramp.
• Stereo - Randomness of the grains' stereo positions.
• Size - Play length of the grain.
• Sync - Synchronizes the size to a tempo-aware beat time.
• Route - Probability of sending grains to route A or route B. Route A is processed by the Multi-effect chain, while B bypasses it.
• Rev. Prob. - Probability of the grain reading from the buffer in reverse.

Harmonic Triangle

Here is where the tonal magic happens. Welcome to the Harmonic Triangle, where ordinary sounds come to life.

The Harmonic Triangle lets you define a given probability for each grain’s pitch, which means you’re able to transpose grains up or down according to user-defined intervals.

The nucleus of this panel is the center triangle and its respective inner node. Each of the triangle’s vertices can transpose the grains within a range of -12 to +12 semitones. The node will determine a three-way probability where the closer the vertex, the greater the chance of a grain picking that vertex’s interval. If the node is in the center of the triangle, all vertices will have the same probability of being picked by the grain for its transposition. Since this is a triangle, you can make triads by setting different intervals on each vertex. This will introduce tonality to the sound, letting you create harmony from simple single note sounds, or even arpeggiated melodic lines from your input.

For a quick triad selection we have added a chord list, with 32 available options, which automatically sets the pitches of the vertexes to match it. You can change them using the list above or by dragging the outer, dashed circle up and down.

If you’re into microtonal sounds or detuning, you can use the free pitch mode which will let you choose continuous values for the transposition.

On the bottom left you can select the pitch quantization mode:

• Quantized - The pitch knobs will be quantized to semitones.
• Free - The pitch knobs will be continuous, letting you fine tune and set microtones.

On the bottom right you can select the interval selection mode:

• Random - Every time a grain is fired, a new interval will be chosen according to the probability of each vertex.
• Fixed - When moving the node, each grain will be assigned an interval according to its proximity to the vertices. These intervals are calculated deterministically and persist until the node is moved to a different position.

The pitch knobs and the X/Y position of the node can be modulated by the LFOs for melodic variation and even more organic and unique results.

Modulator Rack

GRFX has 4 independent LFO modulators which can modulate almost all available parameters.

To modulate a parameter, simply drag the LFO waveform display area and drop it on a modulatable parameter. Modulatable parameters show a brighter background when you initiate the drag interaction. This way you’ll know which parameters can be modulated.

Once you drop the modulator on a parameter you’ll be able to control the amount of modulation to give it. You’ll enter the Quick Modulation mode, shown by a blinking state of the LFO waveform display. When in this mode, rather than setting the base parameter, you’ll be setting the amount of modulation from the selected LFO.

Quick Modulation mode places a white outline overlay over modulated parameters with the selected LFO index in the top left. Selecting other LFOs will show their respective modulation targets.

You’ll see the amount of modulation in the knob in the inside arc, and current value of the base parameter plus its modulation in the outside arc.

To exit this mode, click the LFO waveform display area. You can click it again to return to this mode and adjust modulation values.

Modulations Panel

You can also access the Modulations Panel for a general view of the current modulations by clicking the bottom right icon of the waveform display.

You can see which parameters are being modulated by each LFO and change the corresponding amounts. If you wish to delete modulations, press the bin icon and then the modulations you want to remove.

Parameters

• LFO Selector
• Waveform Display - Visual display of the LFO. To add a modulation, drag and drop it on a modulatable parameter. The bottom right button opens the modulations panel, showing all active modulations.
• Shape - LFO waveshape.
• • Sine
  • Square
  • Saw
  • Triangle
  • Sample & Hold
  • Filtered Sample & Hold
• Phase - Starting phase of the LFO. When Sync is enabled, LFOs reset on the playback start.
• Offset - Change the bias of the values of the waveform. This allows the LFO to gradually change from bipolar to unipolar.
• Rate - Control the frequency of the wave cycle.
• Sync - Synchronize the LFO to the host tempo.

Effect Rack

GRFX has 2 Multi-effect inserts, 2 Sends and a Mixer section.

You can control the probability of each grain entering the Multi-effect section with the Route parameter. They will either go through the effects (route A) or directly to the mixer (route B). There are two linked Multi-effect slots which can be bypassed, along with 2 Sends, a Delay and a Reverb, which can work in series or in parallel by toggling the Link button. Each has independent route A and route B input gains.

In the mixer section you can control the volume of all signal paths plus the overall volume and the plug-in’s dry/wet amount.

The Multi-effect and Send panels have a BYPASS button on the top right which will disable the effect and let the clean signal pass.

FX 1 & 2

The FX slots can have the following effects:

Filter

A Multi-mode filter with 6 different modes.

• Cutoff - Filter cutoff frequency.
• Resonance - Resonance or Q factor of the filter; creates a resonant peak at the cutoff frequency.
• Mode - Filter Mode.
• • Lowpass - A low-pass filter allows low frequency content to pass through, cutting high frequency content.
  • Bandpass - A band-pass filter allows only a restricted frequency band to pass through, attenuating frequencies above and below.
  • Highpass - A high-pass filter allows high frequency content to pass through, attenuating low frequency content.
  • Notch - A notch filter is a filter that cuts a very restricted band of frequencies. The Q factor designates how narrow the band is. Can be used to achieve a phaser-like effect, especially.
  • Peak - A peak filter amplifies a frequency band with the resonance determining the amplification amount, creating a resonant peak at high values.

Distortion

This is a distortion device that can alter the sound from subtle amplification gain saturation to clipping and fuzz effects.

• Drive - Pre distortion input gain.
• Output - Post distortion output volume control.
• Type - Distortion type.
• • Sat - Classic saturation.
  • Fold - Saturated wavefolding; a mix of saturation and sinusoidal wavefolding.
  • Fuzz - Extreme gain and hard clipping for a harsh distortion effect.
  • Nock - Asymmetrical waveshaping that introduces discontinuities in the crest for a very noisy sound.
• Pre HP - Pre distortion highpass filter frequency. Reduces low frequency content prior to distorting.
• Post LP - Post distortion lowpass filter frequency. Reduces high frequency harmonics introduced by the distortion.
• Dry/Wet - Mix between the unprocessed and processed signals.

Delay

A virtual stereo tape delay. This delay has tape emulation controls, a custom filter and stereo parameters.

• Time - Delay tie between the repetitions of the signal.
• Filter - A lowpass and highpass filter control. For negative values, it cuts the high frequency harmonics, while positive values cut the low end.
• Feedback - Amount of the output signal fed back into the circuit.
• Sync - Synchronize the delay time of the host's tempo.
• Stereo - Amount of pan separation between the left and right signals of the output.
• Dry/Wet - Mix between the unprocessed and processed signals.

EQ

Two peak filters with controllable cutoff frequency, gain and Q factor.

• Gain 1 - Amplification/attenuation control of the first frequency band.
• Freq 1 - Cutoff frequency of the filter; determines the centre of the first frequency band.
• Q 1 - Q factor; controls the width of the second frequency band.
• Gain 2 - Amplification/attenuation control of the second frequency band.
• Freq 2 - Cutoff frequency of the filter; determines the centre of the second frequency band.
• Q 2 - Q factor; controls the width of the second frequency band.

Chorus

The chorus effect simulates the subtle pitch and timing differences that occur when multiple musicians or vocalists play the same note, but vary slightly in pitch and timing. This is a stereo chorus, widening the stereo image of the input signal.

• Rate - Frequency of the modulations.
• Time - Delay of the modulated signal.
• Depth - Modulation amount.
• Feedback - Amount of signal to be fed back into the circuit.
• Mode - Switch between the different algorithms.
• • ANA - Analog.
  • DIM - Dimension.
• Dry/Wet - Mix between the unprocessed and processed signals.

Phaser

A phaser introduces a comb filter-like effect by creating a series of notches in the frequency spectrum around a center frequency. This center frequency is modulated by a controllable LFO.

• Centre - Centre frequency of the phaser; notches are grouped around this point.
• Rate - Modulation rate.
• Depth - Modulation depth of the notch frequencies.
• Spread - Control the distance between the notches.
• Feedback - Amount of signal to be fed back into the circuit.
• Dry/Wet - Mix between the unprocessed and processed signals.

Bitcrusher

Degrade the audio bit depth and sample rate, introducing audible quantization error artifacts.

• Bits - Audio bit depth.
• Sample Rate - Audio sample rate.
• Dry/Wet - Mix between the unprocessed and processed signals.

Reverb

This is a reverb effect that can recreate different acoustic spaces from small rooms to long halls.

• Input HP - Cutoff frequency of the highpass filter affecting the input signal.
• Shape Vary between small and large room reflections.
• Decay - Decay rate of the reflections.
• Pre-Delay - TIme between the sound source and the arrival of the first reflections.

Sends 1 & 2

Sends have the same delay and reverb engines as the ones of the FX section with two additional knobs.

• In B - Amount of B signal (grains without FX) input.
• In A - Amount of A signal (grains with FX) input.

The first send has a LINK button which, when enabled, will make both sends work in series.

In this mode, you can only route the signal to the first send, which will then pass to the second send. This allows processing the signal with both delay and reverb. When LINK is disabled, both sends are processed independently.

Mixer

In the mixer panel you can adjust the volumes of the various audio signals for full control of the output.

• A - Volume of the route A signal (grains processed by Multi-effect chain).
• B - Volume of the route B signal (unprocessed grains).
• Volume - Overall output volume.
• Return 1 - Volume of the Delay return signal.
• Return 2 - Volume of the Reverb return signal.
• Dry/Wet - Mix between the unprocessed input and the plugin signal.

The mixer also features a meter in the bottom to monitor the output level of the plugin.

Patch Management

GRFX’s patch manager has a simple layout with banks displayed on the left, the selected bank's patches in the center and the tags pool for patch search filtering on the right.

On the top is the patch bar, which is always visible.

• Left Arrow - Selects the previous patch in the bank.
• Right Arrow - Selects the next patch in the bank.
• Patch Name - Opens/Closes patch browser.
• Save Icon - Opens the patch save dialog.
• Turning Left Arrow - Undo the last action.
• Turning Right Arrow - Redo the last action.
• Revert - Undoes unsaved changes, reverting the patch to its last saved state.

The patch browser’s left side contains three default banks:

• Factory - A selection of built-in patches.
• Local - The default bank where custom patches are saved
• Favorites - Provides a shortcut to all starred/favorited patches.

You can import/export customs banks with the import/export buttons on the bank section and you can also import custom patches to either the local bank or to custom banks using the import button in the patches section.

You can filter your patches either by name, using the search bar, or by tags by using the filter section.

To save a patch, click on the save icon on the top bar. This will open the patch save dialog.

Here you can change the patch name, select the bank where you’ll save it and choose its tags. You can then save it as a new patch (save as), which will create a .gfp file, or you can overwrite an existing patch (save) if you’re using a name that is in use by another patch.

Updated on: 11/03/2026